[PATCH] fortify: Update compile-time tests for Clang 14

Kees Cook
2022-01-30T18:16:19Z

Clang 14 introduces support for compiletime_assert(). Update the
compile-time warning regex to catch Clang's variant of the warning text
in preparation for Clang supporting CONFIG_FORTIFY_SOURCE.

Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: linux-hardening@vger.kernel.org
Cc: llvm@lists.linux.dev
Signed-off-by: Kees Cook <keescook@chromium.org>
---
I'm splitting this patch out of the main Clang FORTIFY enabling patch.
---
scripts/test_fortify.sh | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/scripts/test_fortify.sh b/scripts/test_fortify.sh
index a4da365508f0..c2688ab8281d 100644
--- a/scripts/test_fortify.sh
+++ b/scripts/test_fortify.sh
@@ -46,8 +46,12 @@ if "$@" -Werror -c "$IN" -o "$OUT".o 2> "$TMP" ; then
status="warning: unsafe ${FUNC}() usage lacked '$WANT' symbol in $IN"
fi
else
- # If the build failed, check for the warning in the stderr (gcc).
- if ! grep -q -m1 "error: call to .\b${WANT}\b." "$TMP" ; then
+ # If the build failed, check for the warning in the stderr.
+ # GCC:
+ # ./include/linux/fortify-string.h:316:25: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror=attribute-warning]
+ # Clang 14:
+ # ./include/linux/fortify-string.h:316:4: error: call to __write_overflow_field declared with 'warning' attribute: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror,-Wattribute-warning]
+ if ! grep -Eq -m1 "error: call to .?\b${WANT}\b.?" "$TMP" ; then
status="warning: unsafe ${FUNC}() usage lacked '$WANT' warning in $IN"
fi
fi
--
2.30.2